netfilter: ctnetlink: fix regression in expectation handling
This patch fixes a regression (introduced by myself in commit 19abb7b:
netfilter: ctnetlink: deliver events for conntracks changed from
userspace) that results in an expectation re-insertion since
__nf_ct_expect_check() may return 0 for expectation timer refreshing.
This patch also removes a unnecessary refcount bump that
pretended to avoid a possible race condition with event delivery
and expectation timers (as said, not needed since we hold a
reference to the object since until we finish the expectation
setup). This also merges nf_ct_expect_related_report() and
nf_ct_expect_related() which look basically the same.
Reported-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/include/net/netfilter/nf_conntrack_expect.h b/include/net/netfilter/nf_conntrack_expect.h
index ab17a15..a965280 100644
--- a/include/net/netfilter/nf_conntrack_expect.h
+++ b/include/net/netfilter/nf_conntrack_expect.h
@@ -99,9 +99,12 @@
const union nf_inet_addr *,
u_int8_t, const __be16 *, const __be16 *);
void nf_ct_expect_put(struct nf_conntrack_expect *exp);
-int nf_ct_expect_related(struct nf_conntrack_expect *expect);
int nf_ct_expect_related_report(struct nf_conntrack_expect *expect,
u32 pid, int report);
+static inline int nf_ct_expect_related(struct nf_conntrack_expect *expect)
+{
+ return nf_ct_expect_related_report(expect, 0, 0);
+}
#endif /*_NF_CONNTRACK_EXPECT_H*/
diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
index 3940f99..afde8f9 100644
--- a/net/netfilter/nf_conntrack_expect.c
+++ b/net/netfilter/nf_conntrack_expect.c
@@ -372,7 +372,7 @@
struct net *net = nf_ct_exp_net(expect);
struct hlist_node *n;
unsigned int h;
- int ret = 0;
+ int ret = 1;
if (!master_help->helper) {
ret = -ESHUTDOWN;
@@ -412,27 +412,6 @@
return ret;
}
-int nf_ct_expect_related(struct nf_conntrack_expect *expect)
-{
- int ret;
-
- spin_lock_bh(&nf_conntrack_lock);
- ret = __nf_ct_expect_check(expect);
- if (ret < 0)
- goto out;
-
- nf_ct_expect_insert(expect);
- atomic_inc(&expect->use);
- spin_unlock_bh(&nf_conntrack_lock);
- nf_ct_expect_event(IPEXP_NEW, expect);
- nf_ct_expect_put(expect);
- return ret;
-out:
- spin_unlock_bh(&nf_conntrack_lock);
- return ret;
-}
-EXPORT_SYMBOL_GPL(nf_ct_expect_related);
-
int nf_ct_expect_related_report(struct nf_conntrack_expect *expect,
u32 pid, int report)
{
@@ -440,13 +419,16 @@
spin_lock_bh(&nf_conntrack_lock);
ret = __nf_ct_expect_check(expect);
- if (ret < 0)
+ if (ret <= 0)
goto out;
+
+ ret = 0;
nf_ct_expect_insert(expect);
+ spin_unlock_bh(&nf_conntrack_lock);
+ nf_ct_expect_event_report(IPEXP_NEW, expect, pid, report);
+ return ret;
out:
spin_unlock_bh(&nf_conntrack_lock);
- if (ret == 0)
- nf_ct_expect_event_report(IPEXP_NEW, expect, pid, report);
return ret;
}
EXPORT_SYMBOL_GPL(nf_ct_expect_related_report);